Long ago, Martin discovered he’s a better person when he’s active and fit.

“I realized, in terms of what I’m doing from a job standpoint and life in general, that it was a necessity for me from a mental state,” he says. “When I do a great workout, I feel amazing. Everything works better. My relationships work better, my job. I’m just more efficient.”

These days, his focus is water polo. He started the Carlsbad Masters Water Polo club about six years ago and plays three times a week. But he’s always been an athlete. In high school in Whittier, he swam and played water polo. At Point Loma Nazarene University, he became a surfer and summer lifeguard. In 2006 he took up triathlons, first shorter sprint-distance races, then half-Ironmans and, eventually, completed a full Ironman (2.4-mile swim, 112-mile bike, 26.2-mile run) in 10 hours and 28 minutes. He also qualified for (and completed) the Boston Marathon.

By 2011, he was ready for a fresh challenge, and his son helped steer him in a new direction.

“(He) played water polo at Carlsbad High, and I went to all of his games,” he says. “It’s such a great sport. It’s short, there’s a lot of action. … I started watching and I thought, ‘I want to play water polo again.’ ”

Together they found a group, Old People Water Polo in San Diego, and played for a while. That’s when Martin found that triathlon shape isn’t the same as water polo shape.

“I was gassed,” he says of his first efforts. “I thought, ‘Oh my gosh, this is it. This is my new challenge.’ ”

Martin, who owns part of a software consulting company, works out of a top-floor office in his home. He also keeps weights, a variety of equipment and a stationary bike nearby, so he can squeeze in workouts during his day. The goal: to stay fit, play well in the pool and be able to get the most out of life for as long as possible.

Hayne Palmour IV

Three water polo sessions a week are part of John Martin’s fitness routine.

Three water polo sessions a week are part of John Martin’s fitness routine. (Hayne Palmour IV)

“My goal is, I want to be able to play with my grandkids,” he says. “I don’t want to be in bad health. Let’s take care of this house (body) as it gets older, as long as I can.”

Workout regimen

Aside from three water-polo sessions per week, Martin also takes part in a master’s swimming program, does Orangetheory fitness (which stresses high-intensity interval workouts), runs along the coast near his home and pedals his stationary Peloton exercise bike. “I’ve kind of hung up my road bike,” he says. “It’s just so dangerous. I’ve known five or six people that are dead. You can’t win that.”

Work those legs

For water polo, he needs leg strength. Players tread water using circular egg-beater patterns with their lower legs and feet. That allows them to rise up to catch passes and take shots. “If you don’t have the leg strength, the egg-beatering, I’ll be hanging on guys, all my weight, and they’re still up with the ball. It’s just uncanny leg strength.”

Why water polo?

“In water polo there’s a lot of skill, and I love the team element of it and the strategy,” he says. “To me it’s more of a social thing. It’s working my brain more than triathlon.”

Diet

For several years, he’s followed an intermittent fasting program called Appetite Correction (fast5.org) in which he only eats between the hours of 2 p.m. and 7 p.m. Martin says it allows his body to tap into his fat as a fuel source and work more efficiently. During his eating period, he’ll focus on healthy foods — sometimes. Often, he’ll eat whatever he wants. “I can take down a pint of Ben & Jerry’s,” he says, laughing.

Advice to others

“A key is to not set too big a goal,” he says of exercise. “Consistency is important.”

For those who’ve been inactive, take it easy at first, with whatever it is, be it running, swimming, biking or something else. “Don’t increase more than 10 percent a week and stay with it,” he says. “Don’t give up.”

Williams is a San Diego freelance writer.

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